Note: The quantity (QTY) listed above is the order quantity, not the quantity used; some items are listed as single-quantity because they come in the pack-quantity noted in the item description. The sequential numbers of this list correspond to the numbers in the assembly photos.

Step 2: ASSEMBLE AS PICTURED

Step 3: SETUP

Turn the handle of the 3-way valve (#23) to Position 2 (180 degrees from Position 1) to vent the water tank.

If you are using the same adjustable safety relief valves (#18) that I used, install the appropriate color-coded springs per the instructions that come with the safety valves.

Lift up on the air regulator (#13) adjustment knobs to unlock them if they are in the locked position.

Turn the air regulator adjustment knobs all the way counter-clockwise to bring the regulator set points to 0 PSI.

Loosen the safety valve adjustment locknuts if they are tight.

Turn the safety valve adjustment knobs all the way clockwise to bring the set points as high as possible.

Fill the air tanks to 290 PSI with a compressor, a manual pump or a combination of both through the Schrader valve (#9).

Adjust the regulator that pressurizes the water tank up to 80 PSI.

Adjust the safety valve of that same regulator so that it opens fully at 80 PSI. The pinch valve is rated for 70 PSI water pressure inside the pinch tube, but a safety valve set to open fully at 80 PSI will start to crack open 5 to 10 PSI below the setting.

Adjust the water tank air regulator to 70 PSI or less for operation. Push down on the adjustment knob to lock it.

Adjust the regulator that pressurizes the pinch valve up to 110 PSI. The gauge is located on the pinch valve.

Adjust the safety valve of this regulator so that it opens fully at 110 PSI. The pinch valve is rated for 100 PSI air pressure on the outside of the pinch tube.

Adjust the pinch valve air regulator to 100 PSI or less for operation. Push down on the adjustment knob to lock it. The manufacturer claims that a good seal can be achieved with 15 to 20 PSI above the water pressure setting, but I’ve only been getting a good seal with a ~30 PSI differential.

Step 4: FILL PROCEDURE

Turn the handle of the 3-way valve (#23) to Position 2 to vent the water tank and isolate it from pressurized air.

Fill the air tanks to 290 PSI with a compressor, a manual pump or a combination of both through the Schrader valve (#9).

Remove the nozzle (#43) from the pinch valve pistol, and attach a garden hose or manual pump.*

With the pistol trigger depressed,* fill the water tank to the desired level.

Turn the handle of the 3-way valve to Position 1 to pressurize the water tank. If you did not fill the water tank all the way, this will cause the air tank pressure to drop below 290 PSI.

If applicable, fill the air tanks back up to 290 PSI to maximize air storage (I did not install a gauge on the tanks, I use the gauge that came with the manual pump).

Affix your nozzle of choice, and enjoy.

*Instead of filling through the pistol, you can attach a dedicated fill line (with GHT valve and quick connectors) to the side port on the water tank that I plugged (#26).

Step 5: OPERATION

To fire, simply pull the trigger of the pilot valve (#46). To stop firing, release the trigger.

Keep an eye on the gauge on the pinch valve pistol. When the pressure starts to drop, you know you are low on air.